Pathology of interstitial cystitis.

In this workshop the participants were asked to consider the role of pathology in the diagnosis and management of interstitial cystitis (IC). Currently, the NIDDK definition of IC is made on clinical criteria; bladder biopsy is not required for the clinical work-up and histology is not used as a diagnostic criterion. The literature review described the most common pathological findings to be epithelial denudation or ulceration, mononuclear inflammation, edema, congestion, hemorrhage, and mast cell activation. These pathological changes were not universal or specific with 55% of IC subjects in one study having histology that was normal and indistinguishable from control subjects. Presentations were made which generally confirmed an association between abnormal pathology and more severe disease as determined by symptoms, cystoscopic capacity, and prognosis. During the workshop it was clear that whether or not a biopsy was performed depended on a number of factors, for example, country of origin, the research interest of the unit, and the desire to exclude malignancy on histological grounds. The consensus, which was not unanimous, was that bladder biopsy was a-non-mandatory test in the clinical work-up of the patient with IC but that urine cytology should be performed. It was discussed that bladder biopsy be an optional test and particularly relevant when one was suspicious of other conditions and in IC research. It was hoped that bladder biopsy pathology will give clues to contributory pathogenic processes such as epithelial dysfunction and inflammation; and in the future, with the help of molecular biology, may help determine etiology.